Like all previous games which were a start of a new Generation, Pokémon Black & White introduce new and alternat methods for evolving many Pokémon. These evolutionary methods both enhance upon and even duplicate previous methods. Unlike last time though, there is only one completely new method of evolution.

Pokémon Specific Trade

The main new addition to the Pokémon evolutionary system is a new style of trade evolution. Previously, Pokémon evolving by trade just needed to be traded or have a hold item. However, these new Pokémon only evolve when you trade them specifically with another Pokémon. This explains why their evolutions look slightly different than you think they would with others believing association would be with the other Pokémon.

Although having to trade Pokémon holding items is nothing new, Pokémon Black & White introduce a new item to evolve an old Pokémon. As this game doesn't feature the Beauty stat in any accessible way, it is providing a new alternative in order to evolve Feebas into Milotic..

Location based evolution was introduced during Diamond & Pearl in order to evolve several of the old Pokémon into then-new ones. In subsequent games such as HeartGold & SoulSilver, you were unable to evolve these Pokémon since the areas didn't exist in the games. Although Black & White doesn't have those specific areas in the game, it does provide new alternatives for these evolutions, as detailled below.